Hans a



one part of nitric acid to three parts of sul-.

fu-ric acid in the mixture,

UNITED STATES.

PATENT QFFEQEO HANS A. FRASCII, OF CLEVELAND, OHIO, 'ASSIGNOR TO THEGRASSELLI I CHEMICAL COMPANY, OF SAME PLACE.

BROWN PETROLEUM DYE.

SPECIFICATION forming part of Letters Patent No. 519,036, dated May 1,1894.

Original-application 5185 April 1 1393, iial No 71,018. Divided and thisapplication filed October 24, 1893. Serial No.

489,042. (Specimens) 'zen of the United States, residing atClevel'and,in the county of Cuyahoga andState of Ohio, have inventedcertain new and useful Improvements inProcesses of Producing D ye-Stufis by Nitration; and I do hereby declarethat the following is afull,clear, and exact description of the invention, which will enableothers skilled in the art to which it appertains to make and use thesame.

In the manufacture of anilin, artificial alizarin, and kindred dyestulfs and bases for dyestuifs and colors, coal tar obtained fromilluminating gas works has hitherto been employed. The ordinary processof conversion is by fractional distillation of the coal tar. Thearomatic series of hydrocarbons contained in such coal tar furnishes thesource whence these dyestuffs or colors have been derived. A kindred orsimilar series of hydrocarbons exists also in petroleum or naturalmineral oil or the distillates or derivatives, residual or otherwise,thereof; and it is upon these hydrocarbons of the petroleum series asdistinguished from the hydrocarbons of the coal tar series that I actfor obtaining my new dyestuifs.

My invention relates, first, to a method of obtaining dyestuffs fromhydrocarbons contained in such natural oils by nitration, and,

second, to the product so obtained.

In practicing my invention, I subject crude petroleum or its distillatesor products, residual or otherwise, to the action of a mixture ofsulfuric and nitric acids until all the aromatic hydrocarbons, oletines,naphthenes, and unsaturated hydrocarbons in the oil are taken asoxidized and cor-- up in the acid mixture k I prefer to use respondingnitro products.

and so, also, the propor- Lions may be varied;

to oil may be varied, ac-

tion of acid mixture cording to the quality of the oil being treated,

and according to the quantity of sulfuric and other acids that may be inthe petroleum or its products being treated. Crude oil requires abouttwenty-five per cent., while distillates require from two to ten percent, and sludge 1 parent application, Serial No. 471,018, filed roe butthese pro'por'-' from nothing to five per cent, according to thequantity of acid remaining in the substance.

In all cases, the treatment proceeds alike, substantially as follows:The mixture of acid and oil is agitated, mechanically or by a forcedcurrent of air, at ordinary temperatures, say,

15 to 20 Celsius, until a samplefrom which the acid has been permittedto settle'will discolor little, if any, upon the addition thereto offresh concentrated acid. The mixture of acid and oil is then permittedto rest until the acid is separated from the oil, when the acidcontaining the aromatic hydrocarbons and tarry substances is drawn fromthe oil. The acid mixture taken from the oil is then heated to from to80 Celsius, until the hydrocarbons contained therein are converted intonitro or oxidized products. Nitration may be effected without heat bykeeping the mixture agitated a long time, say, from four to eight weeks,and even longer, thus permitting the acid to act upon the hydrocarbons.The requisite degree or extent of nitration is determined when the bulkof a test sample will dissolve in a hot solution of alkali. The freeacid is then removed and this may be readily accomplished by repeatedlywashing the mixture with cold water or by precipitating the nitrocompound from the acid by a suitable reagent, such as hydrochloric acid.After the free acid is removed, the residuum is heated with water untilthe water is' saturated with the more soluble nitro products. Thesolution is left-to settle, whereby the soluble products and theinsoluble matter and oily matter separate from one another in accordancewith their insolubility and specific gravity. The

soluble products are then drawn ofi and consist in a mixture ofdifferent higher or lower' ceases, whereby a soluble and an insolublecalcium salt are obtained. Any other substance which will form a solubleand insoluble salt with the nitro product may be substituted for thecalcium.

The soluble salt forms the subject of the April 19, 1893, while theinsoluble salt is the subject of this present case, filed as a divisionof said Serial No. 171,018.

The insoluble salt is separated from the solution by filtration or othermeans and may be converted into a soluble salt by the addition theretoof carbonate of sodium, potassium, ammonium, or any other substance thatwill unite therewith and form a soluble com-' pound or dyestuff anddisplace the calcium. This conversion of the insoluble salt into asoluble salt may be eifected by dissolving the insoluble salt in asolution of the carbonate of sodium or other reagents, or by fusing thesalt and its reagent. The dyestuif itself is precipitated from thesolution thereby obtained by the addition of hydrochloric acid, sodiumchlorid, or any other salt in whose solution the dyestufi is insoluble.

The dyestuif obtained is ofa distinct brown colorand in the form of apowder. It has a resinous appearance or texture when first pulverized.This dyestuif is soluble, slightly in cold water, but readily. solublein hot water. It is also soluble in ac etone and glycerin. It for-msaninsoluble calcium salt. It emits the characteristic odor of burning coaloil when highly heated, and dyes cotton, without mordant, a brownishcolor.

If,-instead of using a mixture of sulfuric acidandnitric acid, sulfuricacid be substi tilted-in the processabove described, a sulfo productwill be obtained, The sulfo product made, but can be "referred tq -fnaybe treated to obtain a nitro product by 'dissolving the duct in waterand heating it with nitric acid until efiervescenceceases, after whichthe product is precipitated from the solution as finished sulfo pro- 7before. The same or a similar body may be obtained by the addition to awatery solution of the sulfo product of sodium nitrite and hydrochloricacid, and it can be obtained also by the addition of nitrous acid to thesulfo product.

What I claim is- 1. The art of manufacturing dyestufis from petroleum,natural mineraloils, or the distillates or residuums thereof, whichconsists in nitrating the substance, washing with water, dissolving thenitro products in hot water and decanting or otherwise removing thesolution from the remainder and treating it with a base, such as wiseseparating the insoluble salt thereby formed and rendering it soluble bythe addition thereto of an alkali, such as sodium carbonate, dissolvingit in water and precipitating the dyest'uif from the solution by theaddition of a reagent in whose solution the dye stuff is insoluble, suchas sodium chlorid substantially as described.

2. As an article of manufacture, a dyestufi which isa brown powderderived from petroleum, emitting the characteristic odor of coal oilwhen highly'heated, soluble in water, acetone and glycerin, and capableof dyeing cotton, without'mordant, and whose calcium salt is insolublein water, substantially as described.

Witness my hand to the foregoing specification this 9th day of August,1893.

HANS A. FRASCH.

Witnesses: I

H. 'l. FISHER, GEORGIA SOHAEFFER.

lime, filtering or other-

